Hot air curing oven



March 7, 1967 M. E. MAYNARD 3,307,272

HOT AIR CURING OVEN Filed April 8/1964 s Sheets-Sheet 1 FIG. -4-

INVENTOR.

MA RVI N E MAYNARD BY ATTORNEY March 7, 1967 M. E. MAYNARD 3,307,272

i HOT AIR CURING OVEN Filed April 8, 1964 5 Sheets-Sheet 2 &

INVENTOR MARVMJE.MAYNARD ATTORNEY March 1967- M. E. MAYNARD 3,307,272

HOT AIR CURING OVEN Filed April 8, 1964 s Sheets-Sheet 5 INVENTOR ATTORNEY MARVIN E. MAYNARD United States F'atent ice 3,307,272 HOT AIR CURING OVEN Marvin E. Maynard, Spartanburg, S.C., assignor to Deering Milliken Research Corporation, Spartanburg, S.C., a corporation of Delaware Filed Apr. 8, 1964, Ser. No. 358,345 7 Claims. (Cl. 34-219) This invention relates to a curing oven and more specifically to a curing oven suitable for completion of a chemical reaction on a presensitized, but otherwise finished, gar- .ment.

A recent development in the textile industry has been that of the preparation of durably creased finished garments. The durably creased garments are most often prepared from fabrics which have been presensitized, that is to say, prepared from fabrics, which, when subjected to the proper type of posttreating operation, will retain a durable crease. The presensitized fabrics are usually fabrics which rely upon a coating or impregnant such as for instance, a thermosetting resin or a resin having the ability to cross-link with the chemical structure of the fiber malcing up the fabric. Both the cross-linking type presensitized fabric and the thermosetting resin presensitized type fabrics require the use of a heat-curing operation as the final posttreatment to permanently setting a crease in the finished garment. Durable creases may also be imported to garments prepared from fabrics which are composed of thermoplastic fibers or blends of thermoplastic fibers. The thermoplastic fiber containing garment is creased and the crease made permanent by heating the garment to a temperature approaching the melting point of the thermoplastic fiber.

Due to the fact that the heat treating operation is carried out upon a finished garment, very exacting requirements are made of the apparatus employed for effecting the heat treating operation. The apparatus must be able to maintain those high temperatures which are necessary for curing or cross-linking resins and more specifically the apparatus must be able to maintain temperatures in the range of from about 250 F. to about 375 F. Temperatures within the aforementioned range must be uniform throughout all areas of the garment in order to effect uniform curing. The uniform temperatures must also be maintained without the use of air velocities of an intensity such as to wrinkle or disturb the garment.

It is therefore an object of this invention to provide apparatus for effecting an adequate heat treating operation in a process for the preparation of permanently creased garments. It is another object of this invention to provide heat treating appartus which will maintain substantially uniform temperatures without the use of air velocities of an intensity sufiicient to cause garment wrinkling.

A better understanding of the invention may be had from the following detailed description together with the accompanying drawings in which:

FIGURE 1 is a partially broken front view of the dryer of this invention,

FIGURE 2 is a sectional view taken along the line IIII of FIGURE 1,

FIGURE 3 is a front view of one form of a template member employed in the curing oven.

FIGURE 4 is a front view of the curing oven equipped with an air screen,

FIGURE 5 is a side view taken in the direction of the arrow V of the air curtain of FIGURE 4.

3,37,Z72 Patented Mar. 7, 1967 Referring to FIGURES 1 and 2 of the drawings, the novel curing oven includes an insulated enclosure 2 having a suitable input opening 4 and an output opening 6 at opposite ends of insulated enclosure 2. A continuous conveyor member 3 is mounted so as to provide for the continuous passage of garments 14 through said curing oven. The insulated enclosure 2 has an inner wall member 5, the inner wall member 5 having, at the lower extremity of those portions of the inner wall which are parallel to the direction of garment movement within the oven, a plurality of horizontally aligned, adjustable louver members 7, said louver members 7 having damper blades 22 mounted directly behind said louverrmembers in that portion of free space which exists between the inner wall 5 and the insulated enclosure member 2. Alternatively, simple duct members may be employed for housing the louvers, the ducts extending the length of the walls which are parallel to the direction of garment movement within the oven. Heat is furnished by suitable means, such as for instance, a gas burner 8. The heat generated by burner member 8 is driven downwardly by a blower unit 9 through a perforated ceiling member 10 and from there into the main inner body portion of the insulated enclosure 2. The rate of flow from the blower member 9 may be controlled by means of damper blades 11. The heated air being forced downwardly through ceiling member 10 exits through adjustable louvers 7 and flows rearwardly between inner Wall portion 5 and the outer wall making up the insulated enclosure 2 to the hollow wall portion existing about output opening 6, until the heated air is finally exhausted throngh exhaust duct 12 or returned to the blower through bolwer duct 15, the passage of the heated air being determined by means of damper blades 16 which are regulated according to the temperature requirements of the oven.

Entrance and exit portions 4 and 6 respectively, are preferably equipped with template members 17, template members 17 being secured by a mounting bracket 19 and pin members 18. A better illustration of the template may be seen in FIGURE 3 of the drawings which illustrates a template which is suitable for use in the curing of presensitized trousers. The template member 17 is preferably equipped with notch members 23 which engage pin members 18 mounted on the insulated enclosure 2 of the oven. The template member 17 is also preferably equipped with handle members 24 to facilitate removal of a template member such as, for instance a trouser template member and the substitution of a template member suitable for use with another garment such as for instance a jacket template member. Preferably, the insulated enclosure 2 is provided with bulkhead members 20 which provide a vestibule at the entrance portion 4 and a vestibule at the exit portion 6. Bulkhead members 20 are open, of course, for the passage of garments therethrough and are provided with mounting bracket members 19 and pin members 18 so as to receive .an interior template member 21. The use of vestibules equipped with inner template members provides a better heat seal and also allows the garment to begin cooling before leaving the oven, thereby facilitating the removal of the cured garment at the oven exist portion. To aid in the cooling of the garments 14 before the garments leave the oven, ceiling member 10 is free of perforations in that area above the vestibule at output opening 6, thereby preventing any heated air from being forced directly down on garments 14 while the garments are in the vestibule at exit portion 6.

It should be understood that conveyor member 3 advances garments 14 at a fairly rapid rate and therefore the closure effected at entrance portions 4 and exit portions 6 is a reasonably good closure. The closure effected by the garments themselves is further improved by the use of a template which is cut to the shape of the garment being cured. It is preferred that an air screen be employed with the curing oven in order to still further improve the heat seal at the entrance and exit portions of the oven. An air screen which is suitable for use with the oven of this invention is illustrated in FIGURES 4 and 5. In FIGURES 4 and 5, an air screen is illustrated which is mounted on a presensitized garment curing oven 42. The air screen apparatus comprises a fan member 41 which forces fresh air into duet member 43. Duct member 43 is connected to a U-shaped duct member 47 which is positioned at the entrance 44 of the presensitized garment curing oven 42 and connected to a U-shaped duct member 48 which is positioned at the exit portion 46 of presensitized garment curing oven 42. U-shaped duct members 47 and 48 have elongated openings 49 which are preferably screened openings disposed on the inner portion of either leg of the U-shaped members. Fresh air from fan member 41 is thereby sent through duct member &3 into U-shaped members 47 and 43 wherein the air is ejected from the elongated openings 49 in a manner so as to form a screen across entrance portion 44 and exit portion 46. The presensitized garment curing oven 42 is equipped with U-shaped duct members 50 and El, U-shaped duct members 50 and 51 being interconnected by means of duct member 52. Duct member 52 is connected to exhaust conduit 53 which has an exhaust fan 54 housed therein. Exhaust fan 54 causes air being ejected from elongated openings 49 to be drawn into elongated openings 55 of U-shaped members 50 and 51, respectively. The air drawn into U-shaped members t) and 51 is then carried into duct member 52 and from there into exhaust conduit 53.

Garments which are heat cured with the apparatus of this invention are prepared from fabrics which have been presensitized by means of application of a suitable thermosetting resin or by impregnation with a material having the ability to cross-link the fibers of the fabric. The fabrics which have thus been presensitized are cut, sewn, finished and pressed at temperatures insufficient to eifect either curing of the thermosetting resin or cross-linking of the reactive cross-linking agent. The entire garments are then mounted on the continuous conveyor and continuously passed through the oven which is operated at temperatures sufl icient to elfect complete polymerization of the thermosetting resin or complete cross-linking of the cross-linking agent during that time within which the continuously moving garments are within the curing oven. The temperature range to be maintained within the oven as well as the rate of travel of the continuous conveyor will be determined by the weight of the fabric as well as by the style of the garment and the type of chemical treatment used to effect the presensitization and subsequent permanent crease. Where, for instance, relatively light weight cotton garments are employed which have been cut from fabrics treated with a cross-linking agent, temperatures of about 280 F. may be employed. Where, however, heavier garments prepared from fabrics which have been treated with a thermosetting resin are employed, temperatures as high as about 450 F. may be necessary in order to elfect a complete cure. The rate of travel of the continuous conveyor from entrance point to exit point is usually in the range of from about 5 minutes to about minutes.

Having thus disclosed the invention, what is claimed is:

1. A hot air curing oven for continuously curing presensitized garments comprising a chamber having entrance and exit portions equipped with removable templates cut to the shape of the garment, heater and blower means for directing heated air to said chamber, a continuous conveyor member extending through said chamber and garment members carried by said conveyor,

said garment members effecting a heat seal at the entrance and exit portions of said oven.

2. A hot air curing oven for continuously curing presensitized garments comprising a chamber having an trance and exit portions, said chamber having bulkhead members positioned proximate said entrance and exit portions so as to form exit and entrance vestibules, said bulkhead members equipped with removable templates cut to the shape of the garments, heater and blower means for directing heated air to said chamber, a continuous conveyor member extending through said chamber and garment members carried by said conveyor, said garment members effecting a heat seal at the entrance and exit portions of said oven.

3. A hot air curing oven for continuously curing pre= sensitized garments comprising a chamber having entrance and exit portions, said entrance and exit portions being equipped with air screens and removable templates cut to the shape of said garments, heater and blower means for directing heated air to said chamber, a con tinuous conveyor member extending through said chamber and garment members carried by said conveyor, said garment members and said air screens eifecting a heat seal at the entrance and exit portions of said even.

4. A hot air curing oven for continuously curing presensitized garments comprising a chamber having en trance and exit portions, said entrance and exit portions being equipped with air screens, said chamber having bulkhead members positioned proximate said entrance and exit portions so as to form exit and entrance vestibules, said bulkhead members and said entrance and exit portions being equipped with removable templates cut to the shape of the garments, heater and blower means for directing heated air to said chamber, a continuous conveyor member extending through said chamber and garment members carried by said conveyor said garment members and said air screens effecting at heat seal at the entrance and exit portions of said oven.

5. A hot air curing oven for continuously curin presensitized garments comprising a chamber having inner and outer walls and entrance and exit portions, said entrance and exit portions being equipped with removable templates cut to the shape of the garments, heater and blower means for directing heated air downwardly into said chamber, a continuous conveyor member extending through said chamber and garment members carried by said conveyor, said inner wall having adjustable louvers suitable for exhausting said heated air disposed on those loWer portions of said inner wall which are parallel to said conveyor member, said garment members eifecting a heat seal at the entrance and exit portions of said oven.

6. A hot air curing oven for continuously curing presensitized garments comprising a chamber having inner and outer walls and air screen equipped entrance por tions and air screen equipped exit portions, said entrance and exit portions being equipped with removable templates cut to the shape of the garments, heater and blower means for directing heated air downwardly into said chember, a continuous conveyor member extending through said chamber and garment members carried by said conveyor, said inner wall having adjustable louvers suitable or exhausting said heated air disposed on those lower portions of said inner Wall which are parallel to said conveyor member, said garment members and said air screens effecting a heat seal at the entrance and exit portions of said oven.

7. A hot air curing oven for continuously curing presensitized garments comprising a chamber having inner and outer walls and air screen equipped entrance portions and air screen equipped exit portions, said chamber having bulkhead members positioned within and coupled to said inner wall and positioned proximate said entrance and exit portions so as to form exit and entrance vestibules, said bulkhead members and said entrance and exit portions being equipped with removable templates cut to the shape of the garments, heater and blower means for directing heated air downwardly into said chamber, a continuous conveyor member extending through said chamber and garment members carried by said conveyor, said inner wall having adjustable louvers suitable for exhausting said heated air disposed on those lower portions of said inner wall which are parallel to said conveyor member, said garment members and said air screens effecting a heat seal at the entrance and exit portions of said oven.

References Cited by the Examiner UNITED STATES PATENTS Galloway 342l3 Taliaferro 34242 X Wigglesworth 34-103 Colby.

Hurxthal 34--2l6 X 10 JAMES W. WESTHAVER, Primary Examiner. 

1. A HOT AIR CURING OVEN FOR CONTINUOUSLY CURING PRESENSITIZED GARMENTS COMPRISING A CHAMBER HAVING ENTRANCE AND EXIT PORTIONS EQUIPPED WITH REMOVABLE TEMPLATES CUT TO THE SHAPE OF THE GARMENT, HEATER AND BLOWER MEANS FOR DIRECTING HEATED AIR TO SAID CHAMBER, A CONTINUOUS CONVEYOR MEMBER EXTENDING THROUGH SAID CHAMBER AND GARMENT MEMBERS CARRIED BY SAID CONVEYOR, 